MoS2 has been investigated as a low-cost alternative to Pt in the electrochemical hydrogen evolution reaction. One of the promising methods to further activate MoS2 is phase engineering. MoS2 generally exhibits two kinds of crystalline phases hexagonal 2H phase and octahedral 1T phase. 1T-MoS2 exhibits much better chemical/physical properties than natural semiconductor 2H-MoS2. However, 1T-MoS2 is metastable and its synthesis is still a challenge. Hybrid 1T/2H-MoS2 has been synthesized under relatively mild conditions, but controlling the 1T/2H ratio is still an issue which has not been discussed in detail. In this study, the synthesis methods of hybrid phase 1T/2H-MoS2 with controllable 1T concentration are investigated. The electrochemical hydrogen evolution reaction is then evaluated for 1T/2H-MoS2 with different 1T concentrations by performing both experiments and theoretical calculations.Simulations are used to find the zero temperature jamming threshold, φj, for soft, bidisperse disks in the presence of small fixed particles, or "pins", arranged in a lattice. The presence of pins leads, as one expects, to a decrease in φj. Structural properties of the system near the jamming threshold are calculated as a function of the pin density. While the correlation length exponent remains ν = 1/2 at low pin densities, the system is mechanically stable with more bonds, yet fewer contacts than the Maxwell criterion implies in the absence of pins. In addition, as pin density increases, novel bond orientational order and long-range spatial order appear, which are correlated with the square symmetry of the pin lattice.We propose an asymmetric quasi-solid electrolyte to regulate Li deposition and avoid Li dendrite formation. The thiourea in the electrolyte can absorb on the Li surface to induce Li deposition, change the propagative growth behavior of Li metal and eliminate dendritic formation, thereby ensuring excellent cycling stability and high specific capacity.The frequencies and spectral lineshapes of the stretch and bending modes of water provide invaluable information on the microscopic structures of water in aqueous solutions and at the water/solid interfaces. Density functional theory molecular dynamics (DFT-MD) simulation has been used not only for predicting the properties of water but also for interpreting the vibrational spectra of water. Since the accuracy of the DFT-MD simulations relies on the choice of the exchange-correlation functionals and dispersion correction schemes employed, the predicted vibrational spectra at different levels of DFT theory differ significantly, prohibiting precise comparison of simulated spectra with experimental data. Here, we simulate the vibrational density of states for liquid heavy water based on various DFT-MD trajectories. We find that DFT-MD simulations tend to predict excessive inhomogeneous broadening for the stretch mode of water. Furthermore, we develop a frequency correction scheme for the stretch and bending modes of liquid water, which substantially improves the prediction of the vibrational spectra.Silica nanoparticles (SiNPs) are used in a wide range of consumer products, engineering and medical applications, with likelihood of human exposure and potential health concerns. It is essential to generate toxicity information on SiNP forms and associated physicochemical determinants to conduct risk assessment on these new materials. To address this knowledge gap, we screened a panel of custom synthesized, well-characterized amorphous SiNPs pristine and surface-modified (-C3-COOH, -C11-COOH, -NH2, -PEG) of 5 different sizes (15, 30, 50, 75, 100 nm) for their oxidative potential using an acellular assay. The assay is based on oxidation of dithiothreitol (DTT) by reactive oxygen species and can serve as a surrogate test for oxidative stress. These materials were characterized for size distribution, aggregation, crystallinity, surface area, surface modification, surface charge and metal content. Tests for association between oxidative potential of SiNPs and their physicochemical properties were carried out using analysis of variance and correlation analyses. These test results suggest that the size of amorphous SiNPs influenced their oxidative potential irrespective of the surface modification, with 15 nm exhibiting relatively higher oxidative potential compared to the other sizes. Furthermore, SiNP surface area, surface modification and agglomeration in solution also appeared to affect oxidative potential of these SiNPs. These findings indicate that physicochemical properties are critical in influencing the oxidative behaviour of amorphous SiNPs, with potential to trigger cellular oxidative stress and thus toxicity, when exposed. This information advances our understanding of potential toxicities of these amorphous SiNPs and supports risk assessment efforts and the design of safer forms of silica nanomaterials.A novel alkyne-assisted annulation reaction of MBH-carbonates of propiolaldehydes with α-nitro/bromo ketones is reported, providing a facile synthesis of substituted 2H-pyrans in good yields. This reaction divulges the inimitable reactivity of the MBH-carbonates of propiolaldehydes as C3-synthons wherein the alkyne functionality promoted the reaction without participating in the oxa-[3+3] annulation. https://www.selleckchem.com/products/oligomycin-a.html The obtained products, having alkyne and ester functionalities, allowed further annulations to generate diverse pyrano[3,4-c]pyran-1-ones.To enhance catalytic activity, the present study details a general approach for partial thiolate ligand removal from monolayer-protected clusters (MPCs) by straightforward in situ addition of iodine. Two model reactions are examined to illustrate the effects on the catalytic activity of glutathione (SG)-capped Au MPCs serving as a catalyst for the NaBH4 reduction of 4-nitrophenol to 4-aminophenol and SG-capped Pd MPCs serving as a catalyst for the hydrogenation/isomerization of allyl alcohol. Iodine addition promoted partial thiolate ligand removal from both MPCs and improved the catalytic properties, presumably due to greater surface exposure of the metal cores as a result of ligand dissociation. The rate of 4-nitrophenol reduction increased from 0.066 min-1 in the absence of I2 to 0.505 min-1 in the presence of 2.0 equivalents I2 (equivalents based on total ligated glutathione). The reaction of allyl alcohol to produce 1-propanol and propanal was similarly accelerated as indicated by the increase in turnover frequency from 131 to 230 moles products per moles catalyst per h by addition of 0.